The commonest in this group of conditions are ventricular septal defect, patent ductus arteriosus, and atrial septal defect.


This is the most common cardiac malformation, accounting for 25% of congenital heart diseases. The magnitude of the left to right shunt is determined by the size  of the defect and the degree of the pulmonary vascular resistance.

Clinical Features

  • Small defects with minimal left to right shunts are the most common.
  • Patients are often asymptomatic.
  • The patients may have a loud, harsh or blowing left parasternal pansystolic murmur, heard best over the lower left sternal border on
  • Large defects with excessive pulmonary blood flow and pulmonary hypertension are characterized by;
    • Dyspnoea
    • Feeding difficulties
    • Profuse perspiration
    • Recurrent pulmonary infections
    • Poor growth.

Physical examination

  • Prominence of the left precordium
  • Cardiomegaly
  • Palpable parasternal lift and a systolic thrill, besides a systolic murmur.

Prognosis and Complications

  • Spontaneous closure of small defects occurs in 30% to 50% of cases.
  • A large number remains asymptomatic and a significant number with large defects get repeated infections and congestive cardiac failure.
  • Infective endocarditis is a complication in VSD while pulmonary hypertension may develop as a result of
    high pulmonary blood flow.


  • CXR – Usually normal but some show minimal cardiomegaly and increased pulmonary vasculature
  • ECG – May suggest left ventricular hypertrophy
  • Electrocardiography
  • Echocardiography


  • Control congestive cardiac failure if present.
  • Refer the affected child to the specialized unit.


The pulmonary arterial blood is shunted through the ductus arteriosus into the aorta during foetal life.
Functional closure occurs soon after birth when pulmonary pressure falls. Gradual anatomical closure takes place over several
This process is slower in the preterm infant.

  • Patent ductus arteriosus occurs when ductus fails to close and the blood continues to shunt through it to
    the aorta.

Clinical Features

  • On auscultation one frequently hears a systolic or machinery murmur over the entire precordium, axilla, and back.
  • The patient also has bounding peripheral pulses.
  • The affected child may also be in congestive cardiac failure with its typical clinical manifestations.

There are three types of patent ductus arteriosus:

  • Anatomical defect: This type is the typical ductus that occurs in term and preterm babies and treatment is surgical management.
  • PDA of prematurity: This is basically a “functional” problem in which the ductus remains open when there is tissue hypoxia, e.g., in respiratory distress or anaemia, and is contributed to by fluid overload. The ductus normally closes
    spontaneously or by use of drugs and sometimes surgery may be required.
  • PDA accompanying other abnormalities: Other congenital cardiac abnormalities may be present and may be the only communication between the right and left side of the heart. In such cases closure of the patent ductus
    may lead to death unless the accompanying defects are also corrected.


As for VSD


  • Medical management of CCF if present
  • Refer all children to specialized unit for confirmation of diagnosis and management
  • Medical closure in preterms – indomethacin or ibuprofen